<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>quickSort</title>
</head>

<body>
    <script>
        function quickSort(arr) {
            if (arr.length <= 1) {
                return arr
            }
            let pivotIndex = Math.floor(arr.length / 2)
            let pivot = arr.splice(pivotIndex, 1)[0]
            let left = []
            let right = []
            for (let i = 0; i < arr.length; i++) {
                if (arr[i] < pivot) {
                    left.push(arr[i])
                } else {
                    right.push(arr[i])
                }
            }
            return quickSort(left).concat(pivot, quickSort(right))
        }
        console.log(quickSort([9, 55, 4, 1, -2, 8]))
    </script>
</body>

</html>